_____more countries can use natural energy in the future remains to be seen.

He said it would be at least three more months ________ he could recover and return to school.

His failure in the exam was expected. ________, it was still very disappointing.

------shall we have our picnic tomorrow?-----______it doesn’t rain.

—When did your cousin begin to show his interest in medicine?—It was a Saturday ___ she noticed her uncle experimenting on a frog in his lab.